Daylilies can do really well in potting soil, the question is, how is the drainage of the soil in which the holes were dug? If you have good drainage the daylilies should thrive. I have planted daylilies in three gallon pots solely in potting soil and buried them in the ground for the winter and then pulled the pots in the spring and planted them where I wanted. The roots were great and I got good bloom that season.
My advice; don't worry, be happy!
